Police said investigations were still in its infancy and could not divulge on whether the two men were known to each other.

Det Insp Jameson didn't classify the assault as a one punch incident.

"There was a minor altercation between the two before the punch was delivered but it was one punch that rendered him unconscious," he said.

"But I wouldn't classify it as the traditional one punch, which is unsuspecting."

Det Insp Jameson said alcohol was a factor.

"Once again with the affects of alcohol we have somebody that's in hospital," he said.

This follows the death of Scott Snodgrass in 2013, who suffered severe injuries after he fell to the footpath on Grafton St after a fight, and the death of Ulmarra man Kyle Watkins in 2015 after he was knocked unconscious on West High St during a drunken fight.

"It's the same old story, but it comes with that heeded warning that whilst you're drinking you must drink responsibly," Det Insp Jameson said.

"You must take responsibility for your own drinking as well as what you do whilst you're affected by alcohol and this is an ongoing problem we have in society at this stage."

The ORIGINAL: A MAN was found unconscious after an assault outside the Coffs Hotel.

About 12.30am police were called to West High St, Coffs Harbour.

Police were told by witnesses the man was punched by another man before he fled the area.

The unconscious man was taken to Coffs Harbour Health Campus with injuries to the head. He remains in a serious but stable condition.

Detectives from Coffs/Clarence Local Area Command set up a crime scene and launched an investigation.